As Anna Bay's Joanna Atherfold Finn shopped at the supermarket, her frustration would rise as she noticed all the plastic.
She'd get an overwhelming feeling before reminding herself to be "positive and proactive".
That is, every step taken to reduce single-use plastic is a step forward.
Ms Atherfold Finn will on Wednesday release the book,Plastic Free: The Inspiring Story of a Global Environmental Movement and Why It Matters.
Her co-author is Rebecca Prince-Ruiz, founder of Plastic Free July and one of the world's leading plastic waste experts.
The book tells the story of how Ms Prince-Ruiz founded the campaign, which has grown from 40 participants to 250 million in a decade.
"Plastic Free July is a personal challenge that's part of a global movement to reduce single-use plastic," Ms Prince-Ruiz said.
"The philosophy behind the campaign is that if we all do something - if everyone takes one or two small steps - then together that adds up to make a collective impact."
She said global research shows 8 out 10 people are concerned about plastic waste ending up in landfill and the environment.
"We work closely with a behavioural scientist. The research shows us that facts don't change behaviour.
"A lot of environmental campaigns are so focused on the problem. We talk about the solutions and what people can do at a very personal level. It gives people choice, rather than feeling overwhelmed and disempowered."
Still, she knows some people want to discuss the problem. She's not afraid to do so.
"The statistics show plastics production is set to increase by 40 per cent by 2050," she said.
Already in the first decade of this century, we've used more plastic than the entire last century. We've become a throwaway society."
She deplores plastic being thrown away after a single use when it's "a material that is designed to last forever".
Reducing plastic use is key, along with moving to a circular economy.
If the plastic problem is not addressed, "we're just leaving behind a bigger problem for future generations".
Ms Atherfold Finn said co-writing the book exposed her to "skilled people around the world doing incredible things" to address the plastic disaster.
"One of the most interesting stories in the book for me was Lord Howe Island research, with parents unwittingly feeding their shearwater chicks plastic," she said.
The island was renowned for being pristine.
"That was a big wake-up call. This isn't something that we can say happens in other countries," she said.